EP0264650B1 - Couche antiréfléchissante - Google Patents

Couche antiréfléchissante Download PDF

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Publication number
EP0264650B1
EP0264650B1 EP87113957A EP87113957A EP0264650B1 EP 0264650 B1 EP0264650 B1 EP 0264650B1 EP 87113957 A EP87113957 A EP 87113957A EP 87113957 A EP87113957 A EP 87113957A EP 0264650 B1 EP0264650 B1 EP 0264650B1
Authority
EP
European Patent Office
Prior art keywords
photoresist
reflective coating
substrate
resist
reflective
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP87113957A
Other languages
German (de)
English (en)
Other versions
EP0264650A1 (fr
Inventor
John W. Arnold
Terry L. Brewer
Sumalee Punyakumleard
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Brewer Science Inc
Original Assignee
Brewer Science Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Brewer Science Inc filed Critical Brewer Science Inc
Priority to EP87113957A priority Critical patent/EP0264650B1/fr
Priority to DE8787113957T priority patent/DE3485901T2/de
Publication of EP0264650A1 publication Critical patent/EP0264650A1/fr
Application granted granted Critical
Publication of EP0264650B1 publication Critical patent/EP0264650B1/fr
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/004—Photosensitive materials
    • G03F7/09—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers
    • G03F7/091—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers characterised by antireflection means or light filtering or absorbing means, e.g. anti-halation, contrast enhancement
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/027—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34
    • H01L21/0271—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers
    • H01L21/0273—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers characterised by the treatment of photoresist layers
    • H01L21/0274—Photolithographic processes
    • H01L21/0276—Photolithographic processes using an anti-reflective coating

Definitions

  • the present invention relates to a photolithographic resist having a novel anti-reflective coating, and to processes for producing such a photolithographic resist and integrated circuit elements using such a resist, as well as to a novel composition useful in the production of such a photolithographic resist.
  • the problem is due to a large extent to the limitations of the photographic process used.
  • the layers of chip material, silicon, for example are not perfectly smooth and flat.
  • the uneven topography is of a magnitude approximating that of the wavelength of the light which is used to form the images in the photoresistive material which is applied to the layers of the chip.
  • the light which is used to image the photoresistive material is reflected from the substrate of the chip material, that is, the silicon wafer.
  • This reflection coupled with the uneven topography, causes an uneven distribution of light in the imageable material and results in a large number of artifacts being produced in the developed image. These artifacts cause a large number of rejects in any semi-conductor structure built by current techniques.
  • US-A-4 370 405 discloses a multi-layer resist of the type to which the present invention relates.
  • a resist comprising a substrate on which is deposited a bottom layer "of sufficient thickness (approximately 1.5 micron) to produce a planar top surface".
  • This bottom layer whose thickness in SI units is 1.5 ⁇ m, may contain a dye to reduce reflections, and thus corresponds to the anti-reflective coating of the present invention.
  • a “thin” about 0.1 ⁇ m
  • silicon nitride layer supports a "thin” (about 0.5 ⁇ m) layer of a resist.
  • the anti-reflective layer of the present invention is "thin", in the same sense as the silicon nitride and resist layers of the prior art are “thin”.
  • the present process uses an anti-reflective coating that eliminates deleterious effects due to internal reflections from wafer surfaces and photoresist surfaces.
  • the material offers better adhesion, greater light absorption, is a thinner, more uniform coating, and has a more controlled development and requires fewer process steps than those previously known. Also, it is compatible with and images with the photoresist, in the integrated circuit manufacturing process. The coating leaves less residue on the integrated circuit wafers after development.
  • the present invention thus consists in a photolithographic resist comprising a substrate, a photoresist and a light-absorbing imageable anti-reflective coating between said substrate and said photoresist, characterized in that said anti-reflective coating is a thin, essentially continuous layer of a polybutene sulphone, preferably a polybutene-1-sulphone, containing a dye, the anti-reflective coating being imageable by light of the same wavelength as the photoresist is imageable and being developable and removable with the photoresist.
  • the present invention further consists in a process for preparing said photolithographic resist, in which the anti-reflective coating is deposited and fixed to the substrate by depositing on the substrate a continuous layer of a solution of said polybutene sulphone and baking the product to remove said solvent and fix the resin to the substrate, wherein said solvent is a low surface energy solvent.
  • the invention further consists in a process for making an integrated circuit element by photolithography in which a pattern is imaged in the photoresist and anti-reflective coating of a resist as defined above, the anti-reflective coating imaging with the photoresist, developing and removing the developed image from the photoresist and anti-reflective coating, the imaged anti-reflective coating developing with and being removed with the photoresist, and etching a pattern defined by the imaged anti-reflective coating and photoresist into the substrate to produce said integrated circuit element.
  • the invention still further consists in a solution of a polybutene sulphone and a photolithographic dye in a solvent which is an alcohol, an aromatic hydrocarbon, a ketone or an ester or a mixture of any two or more thereof.
  • the present invention uses a particular polymer, which is such as to allow the use of common organic solvents having low surface (interfacial) energy, which can produced a firmly bonded, thin and consistent coating on a wafer surface.
  • Suitable solvents having low surface energy include alcohols, aromatic hydrocarbons, ketones and ester solvents.
  • Applicants' new material may also incorporate improved dye compounds into the reflective layer.
  • improved dye compounds may also incorporate improved dye compounds into the reflective layer.
  • the use of the dye curcumin (colour index number 75300) or equivalent derivatives, and combinations thereof, to the anti-reflective coating improves the absorption performance of the coating.
  • These, and related dyes absorb strongly in the region of the spectrum (436, 405 nm), where the overlying photoresist is normally exposed and can be removed with the alkaline photoresist developer commonly used, e.g. because of the dye's hydroxyl groups.
  • the combination allows rapid consistent imaging.
  • the dye's excellent solubility in the coating solvents and the dye's strong absorption allow very thin coatings to be used.
  • Applicants' anti-reflective coating can be made further effective by the optional additions of bixin (annatto extract) or other equivalent derivatives such as norbixin to the anti-reflective layer.
  • bixin annatto extract
  • norbixin an equivalent derivatives
  • these dyes absorb strongly in the region of the spectrum at which the photoresist is exposed. These dyes are also readily removed by resist developer, and the carboxylic acid group and other features of these dyes decreases the variations in the rate of removal of the anti-reflective layer due to changes in the baking temperature.
  • Applicants' anti-reflective coating may also be produced in a dry etchable form which also allows patterned images to be formed in the manufacturing process.
  • the vehicle that is used is rapidly removed by dry processing, that is plasma, ion or electron beams.
  • that image is easily and rapidly transferred into the anti-reflective layer by submitting the system to a short dry etch.
  • a middle layer a third layer of a material that is not readily removed by a plasma
  • a system using two layers was also attempted, in which the photoresist was etched and entirely or mostly removed. In this second method the underlying planarizing layer does not etch fast enough to prevent the simultaneous etching of the photoresist.
  • Applicants' dry etchable anti-reflective coating is a relatively thick polymeric layer that planarizes the surface of the wafer and absorbs light that passes through the photoresist. No intermediate etch resistant layer is required, because the light-absorbing planarizing layer is very rapidly removed by dry processes without significant loss of the patterned photoresist layer.
  • the fast etching anti-reflective layer may use the dyes described above.
  • the dyes may be any soluble dye or combination of dyes that has a suitable absorption and is easily removed by a dry process.
  • coumarins and derivatives thereof and equivalent halogenated dyes may be used and are also effective to form an imageable anti-reflective layer.
  • the dry etch imageable anti-reflective coating adds a significant advance in geometry control without adding extra processing steps that lower yield and increase cost.
  • the invention is compatible with photoresist materials and equipment.
  • the dyes used by applicants are those that absorb in the wave length region of the imaging source.
  • the dyes may be included in the anti-reflective coating at a level of from between about 1% to 20%.
  • the film-forming vehicle, the polymer may be present at a level of between about 3% to 20%.
  • the optional addition of water soluble materials may be in concentrations of from between about 0.1% to 10%.
  • the appropriate wetting agents, adhesion promoters, preservatives, plasticizers, and similar additives may be incorporated at the appropriate levels, if desired, and solvent incorporated to balance the composition to 100%.
  • the invention may be used in processes incorporating known techniques of coating substrates, such as spinning to produce film thickness from about 500 angstroms to 40,000 angstroms.
  • the films may be baked at temperatures compatible with existing integrated circuit processes, for example, from about 70°C to 200°C.
  • the baked film may be coated and baked with a photoresist as is known in the art.
  • the photoresist thickness may be whatever is required by the process. These layers are then exposed with light of the known required wavelengths.
  • the films may be developed at the same time with photoresist developer for a time, for example, from about 5 seconds to 5 minutes, or the photoresist may be developed and the underlying film may be removed with a short plasma etch cycle, for example, in an oxygen plasma or other standard plasma process for a period of from about 5 seconds to 5 minutes.
  • the remaining integrated circuit element process may be conducted as prescribed by the known art.
  • the films may be removed by standard photoresist cleanup processes.
  • the invention is further illustrated by the following examples which are included for purposes of illustration from the thousands of actual experiments which have been conducted.
  • the imaged wafers produced have been routinely examined under an electron microscope. The examinations have revealed that the standing wave effect produced by reflected light has been eliminated.
  • anti-reflective coating formulation 8.00 weight per cent poly(butene sulphone) 1.00 weight per cent coumarine 504 (Exciton Co., Dayton, Ohio) cyclopentanone solvent (to balance) a 3 inch (7.6 cm) aluminium-silicon wafer was coated with the anti-reflective coating, using a standard spin coating method, to an average thickness of 2.0 microns. The coated wafer was baked at 140°C for 60 minutes to cure the coating. The coated wafer was allowed to cool and was coated with a photoresist (Shipley AZ1370) by spin coating. The photoresist was cured by baking at 95°C for 30 minutes.
  • the prepared wafer was imaged, using a test resolution pattern and a Cobilt contact printer.
  • the imaged wafer was immersion developed using Shipley's MF312 developer for 20 seconds.
  • the exposed photoresist was removed by the developer and produced a sharp, clear image.
  • the anti-reflective layer was removed by an oxygen plasma (0.2. torr, 100 watts, 20 seconds), while the unexposed photoresist remained with almost no loss in thickness.
  • the image was etched into the substrate of aluminium to produce a sharp pattern of an integrated circuit layer and the remaining photoresist and anti-reflective coating were removed.
  • anti-reflective coating formulation 6.00 weight % poly(butene sulphone) 1.00 weight % of the halogenated dye coumarin 540A (Exciton Co., Dayton, Ohio) cyclopentanone solvent (to balance) a 3 inch aluminium-silicon wafer was coated with the anti-reflective coating, using a standard spin coating method, to an average thickness of 1.5 microns.
  • the coated wafer was baked at 140°C for 60 minutes to cure the coating.
  • the coated wafer was allowed to cool and was coated with a photoresist (Shipley AZ1370) by spin coating. The photoresist was cured by baking at 95°C for 30 minutes.
  • the prepared wafer was imaged, using a test resolution pattern and a Cobilt contact printer.
  • the imaged wafer was immersion developed using Shipley's AZ350 developer for 20 seconds.
  • the exposed photoresist was removed by the developer and produced a sharp clear image.
  • the anti-reflective layer was removed by an oxygen plasma (0.2 torr, 100 watts, 20 seconds), while the unexposed photoresist remained with almost no loss in thickness.
  • the image was etched into the substrate of aluminium to produce a sharp pattern of an integrated circuit layer and the remaining photoresist and anti-reflective coating were then removed.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Architecture (AREA)
  • Structural Engineering (AREA)
  • Photosensitive Polymer And Photoresist Processing (AREA)

Claims (9)

  1. Un résist photolithographique comprenant un substrat, un photorésist et un revêtement antiréfléchissant enregistrable à absorption de lumière entre ledit substrat et ledit photorésist, caractérisé en ce que ledit revètement antiréfléchissant est une couche fine, essentiellement continue, d'un polybutène-sulfone contenant un colorant, hautement soluble dans au moins un hydrocarbure aromatique, une cétone ou un ester ou un mélange de deux de ces substances ou de plusieurs de celles-ci, le revêtement antiréfléchissant pouvant être enregistré par de la lumière de la même longueur d'onde que celle permettant l'enregistrement du photorésist et pouvant être développé et enlevé avec le photorésist.
  2. Un résist selon la revendication 1, dans laquelle le revêtement antiréfléchissant peut être gravé au mouillé.
  3. Un résist selon la revendication 1, dans laquelle le revêtement antiréfléchissant peut être gravé à sec.
  4. Un résist selon la revendication 1, dans laquelle le revêtement antiréfléchissant contient au moins un colorant choisi parmi la curcumine et ses dérivés, la bixine et ses dérivés, les dérivés de la coumarine ainsi que des colorants organiques équivalents halogénés, hydroxylés et carboxylés et des combinaisons de ceux-ci.
  5. Un procédé pour préparer un résist photolithographique selon l'une quelconque des revendications précédentes, dans lequel le revêtement antiréfléchissnt est déposé et fixé sur le substrat par dépôt sur le substrat d'une couche continue d'une solution du dit polybutène-sulfone et par séchage au four du produit en vue d'enlever ledit solvant et de fixer la résine sur le substrat, et dans lequel ledit solvant est un solvant à faible énergie superficielle.
  6. Un procédé selon la revendication 5, dans lequel ledit solvant est un alcool, un hydrocarbure aromatique, une cétone ou un ester ou bien un mélange de deux de ces substances ou de plusieurs de celles-ci.
  7. Un procédé selon la revendication 5 ou la revendication 6, dans lequel le photorésist et la couche antiréfléchissante sont enregistrés simultanément.
  8. Un procédé selon l'une quelconque des revendications 5 à 7, dans lequel le photorésist et la couche antiréfléchissante sont développés simultanément.
  9. Un procédé pour produire un élément de circuit intégré par photolithographie dans lequel une configuration est enregistrée dans le photorésist et le revêtement antiréfléchissant d'un résist selon l'une quelconque des revendications 1 à 4, le revêtement antiréfléchissant étant enregistré avec le photorésist, l'image étant développée et l'image développée étant enlevée du photorésist et du revêtement antiréfléchissant, le revêtement antiréfléchissant enregistré étant développé et enlevé ensemble avec le photorésist, une configuration définie par le revêtement antiréfléchissant et le photorésist enregistrés étant gravée dans le substrat pour produire ledit élément de circuit intégré.
EP87113957A 1982-09-30 1984-04-13 Couche antiréfléchissante Expired - Lifetime EP0264650B1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP87113957A EP0264650B1 (fr) 1982-09-30 1984-04-13 Couche antiréfléchissante
DE8787113957T DE3485901T2 (de) 1984-04-13 1984-04-13 Antireflexionsschicht.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US43179882A 1982-09-30 1982-09-30
EP87113957A EP0264650B1 (fr) 1982-09-30 1984-04-13 Couche antiréfléchissante

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
EP84302692.3 Division 1984-04-13

Publications (2)

Publication Number Publication Date
EP0264650A1 EP0264650A1 (fr) 1988-04-27
EP0264650B1 true EP0264650B1 (fr) 1992-08-26

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EP87113957A Expired - Lifetime EP0264650B1 (fr) 1982-09-30 1984-04-13 Couche antiréfléchissante

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Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5126289A (en) * 1990-07-20 1992-06-30 At&T Bell Laboratories Semiconductor lithography methods using an arc of organic material
JP2694097B2 (ja) * 1992-03-03 1997-12-24 インターナショナル・ビジネス・マシーンズ・コーポレイション 反射防止コーティング組成物
US5294680A (en) * 1992-07-24 1994-03-15 International Business Machines Corporation Polymeric dyes for antireflective coatings
JP3597523B2 (ja) 2002-08-27 2004-12-08 東京応化工業株式会社 リソグラフィー用下地材
TWI358612B (en) 2003-08-28 2012-02-21 Nissan Chemical Ind Ltd Polyamic acid-containing composition for forming a
TW200916965A (en) 2007-10-01 2009-04-16 Jsr Corp Radiation-sensitive composition
KR101368585B1 (ko) 2009-06-15 2014-02-28 제이에스알 가부시끼가이샤 감방사선성 수지 조성물, 레지스트 패턴 형성 방법, 화합물 및 중합체

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4370405A (en) * 1981-03-30 1983-01-25 Hewlett-Packard Company Multilayer photoresist process utilizing an absorbant dye

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1622302A1 (de) * 1968-02-01 1970-10-29 Telefunken Patent Verfahren zum photographischen UEbertragen von Strukturen auf Halbleiterkoerper
JPS5768831A (en) * 1980-10-17 1982-04-27 Fuji Photo Film Co Ltd Heat developable photosensitive material
US4362809A (en) * 1981-03-30 1982-12-07 Hewlett-Packard Company Multilayer photoresist process utilizing an absorbant dye

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4370405A (en) * 1981-03-30 1983-01-25 Hewlett-Packard Company Multilayer photoresist process utilizing an absorbant dye

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Publication number Publication date
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